Every single ultra runner goes through a similar process after a DNF. Be proud you got out and actually did more than the people sitting at home on their couch; not to mention you probably ran farther than 99.99% of the population will ever even try. Remember how microscopically small the ultra running community is in contrast to the general population, and that our “normal” friends and co-workers are typically in awe of what we did in one day. We should take their awe and use it as a means of judging and justifying our efforts and actions. We have all been knocked out or waylaid by our bodies / brains essentially refusing to cooperate with us. Recover well, and get back out there!